A recent study has made a controversial analysis of a fossilized femur, originally excavated from Southwest China’s Maludong (‘Red Deer Cave’) in 1989. The study says that the small leg bone in question originally belonged to an early hominid, such as Homo habilis or Homo erectus, and is only estimated to be 14,000 years old, along with other remains retrieved from the site. However, this find presents a problem for paleontologists: hominids such as this are thought to have gone extinct roughly 1.5 million years ago.

The authors of the joint Australian-Chinese study urge caution in drawing conclusions regarding their findings, due to the wide discrepancy between the relatively young age of the fossil, and the known era these species are supposed to have inhabited. The study details the bone’s features, such as it’s proportions and muscle attachments, all of which correspond to their appearance on earlier examples of H. habilis and H. erectus fossils. The researchers also estimate that the individual would only have weighed 50kg, quite small in comparison to it’s Ice-Age counterparts.

If what this study shows is accurate, then an earlier hominid species managed to survive past their known era 1.5 million years ago, well into the last Ice Age. Co-author Professor Ji Xueping, Yunnan Institute of Cultural Relics and Archaeology, remarks that “it’s young age suggests the possibility that primitive-looking humans could have survived until very late in our evolution, but we need to careful as it is just one bone.”